1. Field of the Invention
The field of the invention is that of control of heat exchangers or boilers, more particularly that type of apparatus when there is a bypass between the inlet and the outlet. Heaters or boilers of typical types are provided with tubes extending between tube sheets with headers at the end of the tubes. The control of the invention is adapted in this type of construction, more particularly wherein there is a bypass between the inlet and the outlet of the heat exchanger.
2. Description of the Prior Art
Heat exchangers or boilers having a bypass between an inlet and an outlet and thermostatic means for controlling flows are common and typical of the prior art. With respect to thermostatically controlled heat exchange systems, reference may be had to the following U.S. Pat. Nos: 1,985,929; 2,211,573; 2,224,240; 2,419,630; 3,751,156; 2,884,197; 3,027,088; 3,148,828; 3,134,366; and 3,224,675.